Film and cameras that are all in one, commonly referred to as single-use or one-time-use cameras, have become well known. Typically, the one-time-use camera is a simple point-and-shoot type comprising a plastic main body part which supports a conventional 35 mm film cartridge in a cartridge receiving chamber, a film take-up spool in a film supply chamber, a fixed-focus taking lens, a film metering mechanism with a rotatably supported metering sprocket that engages the filmstrip, a manually rotatable thumbwheel rotatably engaged with a film spool inside the film cartridge, a single-blade shutter, a manually depressible shutter release button, a rotatable frame counter for indicating the number of exposures remaining for picture-taking, a direct see-through viewfinder, and in some models an electronic flash. A pair of plastic front and rear cover parts house the main body part between them to complete the camera unit. The rear cover part connects to the main body part and/or to the front cover part to make the main body part light-tight. A decorative cardboard outer box or label at least partially covers the camera unit and has respective openings for the taking lens, etc.
To use the one-time-use camera, after the photographer takes a picture he manually rotates the thumbwheel in a film winding direction to similarly rotate the film spool inside the film cartridge. This winds an exposed section of the filmstrip into the film cartridge. The rewinding movement of the filmstrip the equivalent of slightly more than one frame width rotates the metering sprocket in engagement with the filmstrip, to decrement the frame counter to its next lower-numbered setting and to pivot a metering lever into engagement with the thumbwheel to prevent further manual rotation of the thumbwheel. Manually depressing the shutter release button to take another picture pivots the metering lever out of engagement with the thumbwheel to permit renewed rotation of the thumbwheel. When the maximum number of exposures available on the filmstrip are exposed, and the filmstrip is completely wound off the take-up spool and wound into the film cartridge, the one-time-use camera is given to a photofinisher who tears the outer box off the camera unit, separates the rear cover part from the main body part, and removes the film cartridge with the exposed filmstrip from the cartridge receiving chamber. Then, he removes the exposed filmstrip from the film cartridge to develop the negatives and make prints for the customer, and he forwards the used camera parts to the manufacturer for recycling, i.e. remanufacture.
Typically, during original manufacture or recycling (remanufacture) of the one-time-use camera, a film leader protruding from a fresh cartridge is attached to the film take-up spool, the fresh cartridge and the film take-up spool are loaded into the cartridge receiving and film supply chambers, and an intermediate leader section which bridges the film take-up spool and the fresh cartridge is engaged with the metering sprocket. The front and rear cover parts are connected to the main body part and/or to the front cover part to complete the camera unit. Then, an engageable end of the take-up spool which protrudes from the film roll chamber is rotated to factory prewind substantially the entire length of the unexposed filmstrip from the fresh cartridge onto the film take-up spool and to rotate the metering sprocket to increment the frame counter to its total-available frame number setting. Lastly, the outer box or label is placed on the camera unit.
The conventional cartridge typically used in the one-time-use camera has a light-trapping plush, within a film egress/ingress slot, to prevent ambient light from entering the film cartridge through the slot. As contrasted with the conventional cartridge, prior art U.S. Pat. No. 5,357,303 issued Oct. 18, 1994 discloses a new-type cartridge having a spool rotatable in a film winding direction to wind an exposed filmstrip including a trailing film end portion into the film cartridge, and a light lock pivotable to be closed after the trailing film end portion has been wound into the film cartridge. The new-type cartridge can be used in a one-time-use camera. For example, U.S. Pat. No. 5,600,395 issued Feb. 4, 1997 and U.S. Pat. No. 5,614,976 issued Mar. 25, 1997 each discloses a one-time-use camera for use with the new-type cartridge. The new-type camera comprises a thumbwheel manually rotatable in coaxial engagement with the spool inside the film cartridge, in the film winding direction, to similarly rotate the spool to wind the exposed filmstrip including the trailing film end portion into the film cartridge, and a closing actuator coaxially engaged with the light lock to begin to close the light lock when an integral film sensor of the closing actuator senses that the trailing film end portion has been wound into the film cartridge. The thumbwheel is coupled with the closing actuator via a closing lever and a pair of meshing gears to continue to close the light lock when the thumbwheel is further rotated in the film winding direction.
In the new-type camera, the film sensor is adapted to abut the unexposed filmstrip to determine when the trailing film end portion has been wound into the film cartridge. The inherent resistance or stiffness of the unexposed filmstrip against the film sensor operates to prevent the film sensor from being moved, which in turn prevents the closing actuator from being moved to begin to close the light lock. Thus, the film sensor exerts some pressure against the exposed filmstrip.